According to Walters, if the Feng Shui of the site is itself beneficial, based on Form School, a well-defined Dragon (East), Bird (South), Tortoise (North) and Tiger (West), in the location, will increase the beneficial aspects of those parts of the site that receive the location's Qi. If, on the other hand, the site is generally inauspicious, perhaps because there is a lack of Qi but an abundance of Sha (killing), certain unfavourable aspects of the site can be eradicated by the location's favourable position and orientation. That may perhaps be the major performance of the Compass School.